removed the limitation of the next field

diff --git a/modules/src/alloc/alloc.3 b/modules/src/alloc/alloc.3
index 7eac028..e2d6fec 100644 (file)
--- a/modules/src/alloc/alloc.3
+++ b/modules/src/alloc/alloc.3
@@ -67,8 +67,7 @@ All these routines use \fImalloc\fR and \fIrealloc\fR.
 \fIFree\fR can be used on pointers returned by these routines.
 .PP
 \fISt_alloc\fR and \fIst_free\fR provide a mechanism for maintaining free lists
-of structures, whose first field is a pointer called \fBnext\fR.
-This field is used to chain free structures together.
+of structures.
 \fISt_alloc\fR takes three parameters: \fIphead\fR is a pointer to a field
 containing the head of the free list, \fIsize\fR contains the size of the
 structures, and \fIcount\fR indicates how many new structures must be allocated
@@ -93,3 +92,12 @@ malloc(3)
 call a routine \fINo_Mem\fR if there is no memory available. This routine
 is not supposed to return. A default one, that
 gives an error message and stops execution, is provided.
+.SH BUGS
+The
+.I st_alloc
+mechanism only works for structures that are large enough to contain one
+pointer.
+Also,
+.I st_free
+actually is a macro, and references its arguments more than once, so they
+better not have side-effects.

diff --git a/modules/src/alloc/alloc.h b/modules/src/alloc/alloc.h
index 09916a0..612e6b8 100644 (file)
--- a/modules/src/alloc/alloc.h
+++ b/modules/src/alloc/alloc.h
@@ -20,9 +20,17 @@ extern char *malloc(), *realloc();
 
 /*     S T R U C T U R E - S T O R A G E  D E F I N I T I O N S        */
 
+typedef struct _ALLOC_ {
+       struct _ALLOC_ *_A_next;
+} *_PALLOC_;
+
+#define        _A_st_free(ptr, phead, size)    (((_PALLOC_)ptr)->_A_next = \
+                                               (_PALLOC_)(*phead), \
+                                        *((_PALLOC_ *)phead) = \
+                                               (_PALLOC_) ptr)
 #ifndef        BOTCH_FREE
-#define        st_free(ptr, phead, size)       (ptr->next = *phead, *phead = ptr)
+#define st_free(ptr, phead, size)      _A_st_free(ptr, phead, size)
 #else  def BOTCH_FREE
 #define        st_free(ptr, phead, size)       (botch((char *)(ptr), size), \
-                                               ptr->next = *phead, *phead = ptr)
+                                               _A_st_free(ptr, phead, size))
 #endif BOTCH_FREE

diff --git a/modules/src/alloc/st_alloc.c b/modules/src/alloc/st_alloc.c
index 9b76050..56ea4d6 100644 (file)
--- a/modules/src/alloc/st_alloc.c
+++ b/modules/src/alloc/st_alloc.c
@@ -4,18 +4,12 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 /*     st_alloc - get a structure from a free list. If no structures left,
-               create new ones. The structures for which this works are
-               supposed to have as their first tag the string "next", which
-               should be a pointer type.
+               create new ones.
                The counterpart, st_free, is a macro, defined in alloc.h
 */
 
 #include       "alloc.h"
 
-struct xxx     {
-       char *next;
-};
-
 char *
 st_alloc(phead, size, count)
        char **phead;
@@ -28,15 +22,15 @@ st_alloc(phead, size, count)
        if (*phead == 0)        {
 
                p = Malloc(size * count);
-               ((struct xxx *) p)->next = 0;
+               ((_PALLOC_) p)->_A_next = 0;
                while (--count) {
                        p += size;
-                       ((struct xxx *) p)->next = p - size;
+                       ((_PALLOC_) p)->_A_next = p - size;
                }
                *phead = p;
        }
        else    p = *phead;
-       *phead = ((struct xxx *)p)->next;
+       *phead = ((_PALLOC_)p)->_A_next;
        retval = p;
        if (size >= sizeof(long)) {
                q = (long *) p;

diff --git a/modules/src/alloc/std_alloc.c b/modules/src/alloc/std_alloc.c
index 56426f8..d32bd1a 100644 (file)
--- a/modules/src/alloc/std_alloc.c
+++ b/modules/src/alloc/std_alloc.c
@@ -4,18 +4,12 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 /*     st_alloc - get a structure from a free list. If no structures left,
-               create new ones. The structures for which this works are
-               supposed to have as their first tag the string "next", which
-               should be a pointer type.
+               create new ones.
                The counterpart, st_free, is a macro, defined in alloc.h
 */
 
 #include       "alloc.h"
 
-struct xxx     {
-       char *next;
-};
-
 char *
 std_alloc(phead, size, count, pcnt)
        char **phead;
@@ -28,15 +22,15 @@ std_alloc(phead, size, count, pcnt)
 
                p = Malloc(size * count);
                *pcnt += count;
-               ((struct xxx *) p)->next = 0;
+               ((_PALLOC_) p)->_A_next = 0;
                while (--count) {
                        p += size;
-                       ((struct xxx *) p)->next = p - size;
+                       ((_PALLOC_) p)->_A_next = p - size;
                }
                *phead = p;
        }
        else p = *phead;
-       *phead = ((struct xxx *) p)->next;
+       *phead = ((_PALLOC_) p)->_A_next;
        p += size;
        while (size--) *--p = 0;
        return p;